The HHR SS Models equipped with the 5-speed manual transmission are capable of withstanding a high amount of torque, and transferring it to the wheels especially. If your car is equipped with the G85 Limited Slip Differential, you will also exhibit less torque steer than those models who do not.

Stock power output of the Manually Equipped HHR SS is about 260 horsepower and 260 pounds of torque. This translates typically to about 240 wheel horsepower and about 250 pounds of torque at the wheels, meaning that the factory tune is likely underrated a little bit.

Our Stage 1 tunes produce 290 to 310 wheel horsepower and 340 to 370 wheel torque, depending on modifications. This is a peak increase of 50 to 70 wheel horsepower, and 90 to 120 wheel torque over stock.

Those HHR SS equipped with the 4-speed Automatic Transmission have some limitations to the amount of torque that the powertrain can reliably handle. For this reason, GM released the Automatic Equipped HHR SS models with less horsepower and torque than the manual transmission cars. We also specially tune these Automatic equipped cars with extra powertrain safety in mind.

The stock power output of the automatic HHR SS is around 220 horsepower, and our Stage 1 tunes will boost this up to around 280 horsepower, which is only slightly less peak horsepower than the manually equipped cars, but we cap the torque output of the automatic tunes for the HHR SS at around 300-310 pounds of torque instead of the 340-360 pounds of torque that we produce on the manual transmission cars.

In addition to tuning the engine on the automatic equipped HHR SS, we also re-tune the transmission tables as well to quicken the shift times up by about 0.25 seconds per shift, as well as increase the shift pressure to limit torque converter slippage in between high rpm shifts. This will result in increased acceleration, even without all of that additional power from the engine tune alone, at no additional cost!